The main difference between PayPal Mpesa and PayPal Equity is that you cannot deposit (top-up) money from Equity Bank to PayPal but you can deposit Money from Mpesa to PayPal.
It is quick to withdraw money from PayPal to Mpesa compared to PayPal to Equity Bank
The main benefit of using PayPal to Equity Bank is that its transaction fees are low compare to Mpesa PayPal
PayPal to Mpesa will also not be your choice if there is mismatch in your Mpesa and PayPal names